Knob attachment



(ModeL) W. I. ALVORD,

KNOB ATTACHMENT. Patented Nov. 10, 1885.

UNIT D STATES PATENT Crunch.

WILLISTON I. ALVORD, OF BRIDGEPORT, CONNECTICUT.

-KNOB ATTACHMENT.

EPECEPIC'ATION forming part of Letters Patent No. 330,186. datedNovember 10, 1885.

Application filed April 16, 1885. Serial No. 162,404.

To aZZ whom it may concern:

Be it known that I, WILLISTON I. ALVORD,

a citizen of the United States, residing at Bridgeport, in the county ofFairfield and State of Connecticut, have invented certain new and usefulImprovements in Knob Attachments; and I do hereby declare the followingto be a full, clear, and exact description of the invention, such aswill enable others skilled in the art to which it appertains to make anduse the same.

Myinvention relates to certain new and use ful improvements in knobattachments, and has for its object to provide a simple device wherebythe knob-shanks may be readily inserted and held within the lock; andwith these ends in view my invention consists in the details ofconstruction and combination of elements hereinafter fully explained,and then specifically designated by the claim.

In order that those skilled in the art to which my invention appertainsmay fully understand its construction, I will describe the same indetail, referring by letter to the accompanying drawings, forming a partof this specification, in which Figure l is an end elevation of thelatchhub; Fig. 2, a central cross-section, showing the arms inelevation; Fig. 3, a central longitudinal section of the hub; Fig. 4:,aperspec tive View of the knob-shank; Fig. 5, a central longitudinalsection of the hub having the shanks therein, and shown with thehub-arms in elevation, and Fig. 6 a section showing a different form ofhead and recesses in thehub.

Similar letters denote like parts in the several figures of thedrawings.

A is the latch-hub, having the arms B projecting therefrom. This hub isjournaled, as are ordinary hubs,in the two shells of the lock, and thearms engaging with lugs upon the yoke at the rear of the latch-boltretract the latter when the hub is turned. This retraction of the boltby the contact of the arms with the yoke-lugs forms no part of myinvention, whose purpose is to provide simple and efficient means forthe attachment of the knobs. The opening through the hub isirregular,and its peculiarities are as follows: In the center of the hubis a recess, 0, circular in cross-section and concentric with theoutside contour (Model.)

of the hub. Upon either side of this central recess, and formed in theinner surface of the hub, are eight triangular cavities, D, so that theopening at these points of the hub is in shape an eight-pointed star. Ateither end of the hub the opening outward is a square, the corners ofwhich are coincident with four alternate points of the star-shapedorifice just mentioned.

The peculiarities of contour just described will be readily understoodby reference to Figs. 2 and 3, and the purpose of said peculiaritieswill be presently explained.

F is the shank, square in cross-section, but turned to oylindric form atG,so as to leave the extremity square, as at H. In adjusting theknob-shank its head isinsertedwithintheopening whose interior contourhas been set forth. In its entrance it passes through the square, andthrough the star-shaped opening behind it, into the circular recess inthe center of the hub. It is then turned one-eighth of a turn andwithdrawn into the square recess made by the four alternate cavitieswhich do not coincide with the corners of the square opening E. By thewithdrawal of the head into the square just mentioned the central recessis left clear,so that the opposite shank-head may be inserted, turned,and withdrawn in the manner just explained. The square heads fit tightlywithin the recesses, and the hub is readily turned by the turning oftheshank.

In Fig. 6 I have shown another form of head, X, which I am able to useequally well with the square by changing the internal contour of the hubto correspond with its peculiar shape.

In my invention I do not wish to be confined to the exact shape of headand recesses shown and described, for I can employ any form of headother than round-as elliptic or triangulartogether with an interiorcontour of the hub to correspond therewith.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

In a knob attachment, the combinatiomwiih the shanks provided withheads, as described, of a hub whose central longitudinal opening is asfollows: in the center a recess within which one of the heads may turn,upon either side thereof a second recess formed by cav-if Ill-testimonywhereof I affix my signature in ties in the walls and corresponding withsaid presence of two witnesses.

heads, and upon either side of the last-named recesses openingsoutthrough the ends of the WILLISTON I. ALVORD. hub,als0 corresponding inshape to the heads and having anglescr corners coinciding withWitnesses:

each alternate angle or corner of the recess S. S. WILLIAMSON,

next within, substantially as set forth. H. T. SHELTON, Jr.

